Composite movement table apparatus

Abstract

By operating a Z direction position adjustment mechanism by a driving motor, a Z table movable in the X and Y directions can be moved in a Z direction while maintaining its horizontal condition. Vibrations caused in the Z table when the Z table is moved at a high speed in the X and Y directions are damped by vibration damping means provided between the Z table and a base bed fixed to a coarse adjustment table which is mounted on a base and driven in the X and Y directions. Improvement in the accuracy of positioning in the X and Y directions is achieved, as well as a vibration damping effect. A chuck holding member is formed on the table to hold a chuck by suction which in turn holds a mounted member by suction, thereby making the exchange of the chuck easy and preserving the parallelism of the upper surface of the chuck.

I claim: 
     
       1. A composite movement table apparatus capable of moving at least in a Z axis direction, comprising: a coarse adjustment table mounted on a base and driven in an X axis and a Y axis direction;   a base bed mounted on said coarse adjustment table;   a Z table movable in the X axis and Y axis directions as well as in the Z axis direction;   a Z direction position adjusting mechanism fixed to said base bed for adjusting the position of said Z table in the Z axis direction relative to said base bed, said Z direction position adjusting mechanism supporting said Z table;   vibration damping means provided between said Z table and said base bed for damping vibrations caused in said Z table during movement thereof in the X axis and Y axis directions; and   a driving mechanism for actuating the Z direction position adjusting mechanism in the Z axis direction including a driving motor fixed to said base bed.   
     
     
       2. The apparatus of claim 1 wherein said Z direction position adjusting mechanism includes a slant guide section formed on said base bed, an oblique slider movable by being guided by said slant guide section and having a horizontal upper surface, and a driving mechanism for driving said oblique slider to advance and to retract along said slant guide section. 
     
     
       3. The apparatus of claim 2 wherein said slant guide section includes a cross roller guide, and said driving mechanism is provided with a screw type feeding device including a screw shaft having an axis parallel to said slant guide section and being driven into rotation by the driving motor. 
     
     
       4. An apparatus according to claim 1 wherein said Z table is mounted on said Z direction position adjusting mechanism by means of a rolling element with retainer so that said Z table is movable horizontally with respect to said Z direction position adjusting mechanism. 
     
     
       5. The apparatus of claim 1 wherein said Z table is resiliently coupled with a fine adjustment XY movement table supported by the base bed, and said vibration damping means includes a vibration damping section having a vibration damping surface parallel to a movement surface formed on said XY movement table, a receiving surface formed on said base bed and opposed to and in close proximity to said vibration damping section, and a viscous fluid interposed between said receiving surface and said opposed vibration damping surface, said viscous fluid filling a space between said receiving surface and said vibration damping surface with a depth of said viscous fluid equal to or less than the space therebetween, thereby providing a damping effect to said vibration damping surface.   
     
     
       6. The apparatus of claim 5 wherein said vibration damping surface and said receiving surface are formed at each of both side portions of said XY movement table. 
     
     
       7. The apparatus of claim 5 wherein said viscous fluid is a silicone oil having a high viscosity. 
     
     
       8. The apparatus of claim 5 wherein a leaf spring is provided between said Z table and said XY movement table to urge said Z table in the X axis direction towards said oblique surface slider. 
     
     
       9. The apparatus of claim 1 wherein a chuck holding member is disposed on said Z table, a suction chuck for holding an exposed member of an exposure device is removably held on said chuck holding member, a recess forming a tightly enclosed space is formed at an abutting portion between said chuck and said chuck holding member, and said recess communicates with gas suction means. 
     
     
       10. The apparatus of claim 6 wherein said viscous fluid is a silicone oil having a high viscosity.